It is well known in the automatic coating art to convey motor vehicle bodies through a spray booth where preprogramed lacquering robots or the like automatically move a spraying device relative to the body. An operation controlling computer program is usually generated using the well-known teach-in method preparatorily preformed during the coating of an initial body introduced into the spray booth for this purpose. According to prior art teaching, it is assumed that subsequent bodies are conveyed through the spray booth in the exact position, relative to the spraying device, as the initial body was during the teach-in programing operation. Therefore, efforts were made to position the subsequent vehicle bodies traveling along in the conveyor as accurately as possible relative to the spraying device.
When coating bodies according to the prior art teaching, unacceptable position tolerances could only be avoided by providing high cost conveying equipment which very accurately positioned each vehicle body for coating. For example, the cost of providing acceptable carriages, or so-called skids, for a floor mounted conveyor system or the appropriate suspension equipment for an overhead conveyor system which prevent the positional deviations causing coating defects would be inhibitive. Thus, coating defects due to positional tolerance deviations between the body and spraying device have been accepted as inevitable in this art.